U.S. patent application number 12/649523 was filed with the patent office on 2010-12-23 for camera module with liquid crystal module.
This patent application is currently assigned to HON HAI PRECISION INDUSTRY CO., LTD.. Invention is credited to Chi-Wei Chiu.
Application Number | 20100321595 12/649523 |
Document ID | / |
Family ID | 43354033 |
Filed Date | 2010-12-23 |
United States Patent
Application |
20100321595 |
Kind Code |
A1 |
Chiu; Chi-Wei |
December 23, 2010 |
CAMERA MODULE WITH LIQUID CRYSTAL MODULE
Abstract
An exemplary camera module, includes a lens group, an image
sensor, and a liquid crystal module disposed between the lens group
and the image sensor. The liquid crystal module includes a first
glass substrate adjacent to the image sensor, an opposite second
glass substrate, a plurality of liquid crystal molecules arranged
between the first glass substrate and the second glass substrate, a
first transparent electrode layer formed on the first glass
substrate and facing the liquid crystal molecules, and a second
transparent electrode layer formed on the second glass substrate
and facing the liquid crystal molecules. The liquid crystal
molecules are configured for adjusting light path of the light
transmitting therethrough in response to an electric field between
the first and second transparent electrode layers, thus adjusting
depth of field of the camera module.
Inventors: |
Chiu; Chi-Wei; (Tu-Cheng,
TW) |
Correspondence
Address: |
Altis Law Group, Inc.;ATTN: Steven Reiss
288 SOUTH MAYO AVENUE
CITY OF INDUSTRY
CA
91789
US
|
Assignee: |
HON HAI PRECISION INDUSTRY CO.,
LTD.
Tu-Cheng
TW
|
Family ID: |
43354033 |
Appl. No.: |
12/649523 |
Filed: |
December 30, 2009 |
Current U.S.
Class: |
349/2 |
Current CPC
Class: |
H04N 5/2257 20130101;
H04N 5/2254 20130101; H01L 27/14625 20130101 |
Class at
Publication: |
349/2 |
International
Class: |
G02F 1/13 20060101
G02F001/13 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 18, 2009 |
CN |
200910303416.X |
Claims
1. A camera module, comprising: a lens group; an image sensor; and
a liquid crystal module disposed between the lens group and the
image sensor, the liquid crystal module comprising a first glass
substrate adjacent to the image sensor, an opposite second glass
substrate, a plurality of liquid crystal molecules arranged between
the first glass substrate and the second glass substrate, a first
transparent electrode layer formed on the first glass substrate and
facing the liquid crystal molecules, and a second transparent
electrode layer formed on the second glass substrate and facing the
liquid crystal molecules, the liquid crystal molecules being
configured for adjusting light path of the light transmitting
therethrough in response to an electric field between the first and
second transparent electrode layers, thus adjusting depth of field
of the camera module.
2. The camera module as described in claim 1, further comprising an
IR-cut filter formed on the second glass substrate.
3. The camera module as described in claim 1, wherein the image
sensor is proximate to the first glass substrate.
4. The camera module as described in claim 3, wherein the first
glass substrate is disposed on the image sensor.
5. The camera module as described in claim 3, wherein a gap is
maintained between the first glass substrate and the image
sensor.
6. The camera module as described in claim 1, wherein all areas of
the first transparent electrode layer are applied a same first
voltage.
7. The camera module as described in claim 6, wherein all areas of
the second transparent electrode layer are applied a same second
voltage different from the first voltage.
8. The camera module as described in claim 1, wherein both of the
first and second transparent electrode layers are circular.
9. A camera module, comprising: a lens group; a barrel receiving
the lens group therein; a holder threadedly engaged with the
barrel; an image sensor and a liquid crystal module received in the
holder, the liquid crystal module disposed in front of the image
sensor, the liquid crystal module comprising a first glass
substrate adjacent to the image sensor, an opposite second glass
substrate, a plurality of liquid crystal molecules arranged between
the first glass substrate and the second glass substrate, a first
transparent electrode layer formed on the first glass substrate and
facing the liquid crystal molecules, and a second transparent
electrode layer formed on the second glass substrate and facing the
liquid crystal molecules, the liquid crystal molecules being
configured for adjusting light path of the light transmitting
therethrough in response to an electric field between the first and
second transparent electrode layers, such that the light
transmitting through the liquid crystal module focuses on a desired
position.
10. The camera module as described in claim 9, further comprising
an IR-cut filter formed on the second glass substrate.
11. The camera module as described in claim 9, wherein the image
sensor directly faces the first glass substrate.
12. The camera module as described in claim 11, wherein a gap is
maintained between the first glass substrate and the image sensor.
Description
BACKGROUND
[0001] 1. Technical Field
[0002] The present disclosure relates to camera modules, and
particularly, to a camera module having liquid crystal module
mounted therein.
[0003] 2. Description of Related Art
[0004] Camera modules usually include lens groups, apertures, and
image sensors.
[0005] In camera modules, depth of field is the range of distance
within the field of view of the camera that is in focus at the
current settings. The depth of field varies depending on aperture
value, focal length as well as viewing distance. In some cases, it
may be desirable to have the entire field of view sharp, and so
maximum depth of field is appropriate. In other cases, a small
depth of field may be more effective, emphasizing the subject while
deemphasizing the foreground and background.
[0006] In a typical camera module, for a given aperture value,
viewing distance, and other related parameters, the depth of field
of the camera module cannot be changed.
[0007] What is needed therefore, is a camera module to overcome the
above-mentioned shortcoming.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] Many aspects of the present camera module can be better
understood with reference to the following drawings. The components
in the drawings are not necessarily drawn to scale, the emphasis
instead being placed upon clearly illustrating the principles of
the present camera module. Moreover, in the drawings, like
reference numerals designate corresponding parts throughout the
several views.
[0009] FIG. 1 is a schematic view of a camera module in accordance
with a first embodiment.
[0010] FIG. 2 is a plan view of the second transparent electrode
layer of FIG. 1.
[0011] FIG. 3 is a schematic view of a camera module in accordance
with a second embodiment.
DETAILED DESCRIPTION
[0012] Embodiments of the present camera module will now be
described in detail below and with reference to the drawings.
[0013] Referring to FIG. 1, a camera module 10 in accordance with a
first embodiment, is shown. The camera module 100 includes a holder
11, a barrel 12, a lens group 120, an image sensor module 15, an
image sensor 13, a liquid crystal module 14, and an IR-cut filter
16.
[0014] The lens group 120 includes a first lens 122, a second lens
124, and an aperture 126 sandwiched directly between the first lens
122 and the second lens 124. The lens group 120 is received in the
barrel 12. The barrel 12 and the holder 11 are threadedly engaged
by the threads 111, 121 respectively formed thereon.
[0015] The image sensor 13, liquid crystal module 14, and IR-cut
filter 16 are received in the holder 11. The image sensor 13 can be
CCD or CMOS. The liquid crystal module 14 includes a first glass
substrate 141 adjacent to the image sensor 13, an opposite second
glass substrate 142, a plurality of liquid crystal molecules 143
arranged between the first glass substrate 141 and the second glass
substrate 142, a first transparent electrode layer 144 formed on
the first glass substrate 141, facing the liquid crystal molecules
143, and a second transparent electrode layer 145 formed on the
second glass substrate 142, facing the liquid crystal molecules
143. The IR-cut filter 16 is formed on the second glass substrate
142, directly facing the lens group 120 and the barrel 12.
[0016] Preferably, the image sensor 13 directly faces the liquid
crystal module 14, i.e., the image sensor 13 is proximate to the
liquid crystal module 14. Light transmitting through the liquid
crystal module 14 is received by the image sensor 13. In the
present embodiment, the liquid crystal module 14 is directly
disposed on the image sensor 13. The first and second transparent
electrode layers 144, 145 cooperatively form at least a voltage
difference therebetween, thereby applying an electric field on the
liquid crystal module 14. All areas of the first transparent
electrode layer 144 can be applied a same first voltage, and all
areas of the second transparent electrode layer 145 can be applied
a same second voltage which is different from the first voltage.
Alternatively, a same voltage may be applied to all areas of the
first transparent electrode layer 144, but voltage differences are
maintained between areas of the second transparent electrode layer
145.
[0017] The first and second transparent electrode layers 144, 145
can have the same shape. In the present embodiment, the first and
second transparent electrode layers 144, 145 are circular.
Referring also to FIG. 2, the second transparent electrode layer
145 includes a circular electrode 1450, a first ring-shaped
electrode 1451, a second ring-shaped electrode 1452, a third
ring-shaped electrode 1453, and a fourth ring-shaped electrode
1454. The circular electrode 1450, first ring-shaped electrode
1451, second ring-shaped electrode 1452, third ring-shaped
electrode 1453, and fourth ring-shaped electrode 1454 are
concentrically arranged in sequence from the center of the second
glass substrate 142 to the periphery of the second glass substrate
142, with a gap 1455 maintained between each two adjacent
electrodes. Widths d.sub.1, d.sub.2, d.sub.3, d.sub.4, d.sub.5 of
the circular electrode 1450, first ring-shaped electrode 1451,
second ring-shaped electrode 1452, third ring-shaped electrode
1453, and fourth ring-shaped electrode 1454 are in a relationship
of d.sub.1>d.sub.2>d.sub.3>d.sub.4>d.sub.5. The first
transparent electrode layer 144 is formed the same as the second
transparent electrode layer 145. The corresponding electrodes of
the first and second transparent electrode layers 144, 145
cooperatively form a voltage difference therebetween, thereby
applying an electric field on the liquid crystal molecules 143
located therebetween.
[0018] In other embodiments, the first and second transparent
electrode layers 144, 145 can be in different shapes. For example,
the second transparent electrode layer 145 is plate shaped, and the
first transparent electrode layer 144 is formed into a dot
array.
[0019] The liquid crystal molecules 143 are capable of rotating
when the electric field applied thereto is changed, thus the liquid
crystal molecules 143 are rearranged. The liquid crystal molecules
143 present different refraction rates to the light projected
thereon in different arrangements thereof. In this way, the liquid
crystal molecules 143 are capable of adjusting light path of the
light, and thus the light transmitting therethrough can focus on a
desired position along the optical axis of the camera module 10.
That is, a focal length of the entire camera module 10 can be
changed.
[0020] The focal length influences depth of field of the camera
module 10. In application, for a given aperture value and viewing
distance, the depth of field will be determined by the focal
length, the greater the focal length, the greater the depth of
field. That is, the depth of field of the camera module 10 can be
changed by the liquid crystal module 14.
[0021] It is understood that the change of the depth of field also
leads to change of depth of focus. That is, once the image sensor
13 is disposed within the depth of focus, the images formed by the
image sensor 13 would have acceptable sharpness.
[0022] Referring to FIG. 3, a camera module 20 in accordance with a
second embodiment, is shown. The camera module 20 is essentially
similar to the first camera module 10 illustrated above, the only
difference is that a gap 25 is maintained between the image sensor
23 and the liquid crystal module 24.
[0023] It is understood that the above-described embodiments are
intended to illustrate rather than limit the disclosure. Variations
may be made to the embodiments and methods without departing from
the spirit of the disclosure. Accordingly, it is appropriate that
the appended claims be construed broadly and in a manner consistent
with the scope of the disclosure.
* * * * *